Tsx536

I have a screen hooked up in my car and I hook up my portable Audio/video player to it. I noticed that when I have the power for my audio/video player running off of the cigarette lighter, then I get interference in my video picture.

Does anyone know how to prevent this?
Basically lines go across the screen and it looks like as if you were using regular rabbit ear antennas on a TV and you were trying to get a channel that is out of range.

Thanks...Kenny

elduderino

I assume that this only happens when using the cig adapter AND the car is running...

If you only get the noise when you use the cig adapter, the simplest thing to do long term is to install an in-line noise filter in series with your cig adapter-socket power wire.

Tsx536

Hey Elduderino,

Nice to see you back here posting man!
I think you were only gone a week and every1 already started asking...where u've been at ....Haha..

The interference is actually in the video picture not in the sound.

I ended up getting the Pioneer N1 installed in the storage compartment area. I'm actually really happy with it!! I will post pictures when I can. Everything is not totally complete on the intsall quite yet, but when I get everything finished...I'll post pics!

elduderino

Noise is noise, Kenny.

e_lectro

Well, don't feel to bad about the cig lighter noise... almost everyone who uses it for power, be it audio or video, ends up with noise. It's just a crappy unfiltered source.

Tsx536

Yeah...that's too bad !! Oh well..

I did notice something interesting. If I hook up the Portable video player to a Power inverter and then use the standard AC plug there is no interference in the video. So at least I can go that route if all else fails.

So an inline filter should eliminate the video interference?

Is this what I need?
http://www.crutchfield.com/S-sA4Bp7c....asp?i=003S15A

Or what about this?
http://www.partsexpress.com/pe/showd...number=079-044


Is here anything that I could get which just plugs into the RCA, similar to how a ground Loop isolator works?

e_lectro

The power inverter has a built in power filter, takes care of the problem for you. But you are wasting a ton of extra power.... no sence turning DC into AC just to turn it back into DC.

Try the N-500 filter from this page: http://davidnavone.com/filters.html
OR just hit radio shack for one.

Tsx536

Thanks for the response.

Looks good....So what connections need to be made for this filter? I can't tell from the picture.

e_lectro

Just power and ground. Unfiltered car power in - filtered power out to video device.

Tsx536

So I would just basically hook it up in series with the power and ground that plugs into the cigarette lighter?

I just looked and I have a really really old Inline filter, but it says that it's 20 amp. Is it bad too put too big of one?

Also, I'm guessing I bought it from radio shack about 7 years ago, do you think that matters?

Thanks for the help!

e_lectro

No such thing as too big. Give it a try and see what heppens. Hook it up just like you said.

nshom

I use the cig lighter in the armrest to power a screen and I don't have any problems.

elduderino

Hence the "almost", dude.

Tsx536

Well, I don't have any video problems powering my extra LCD screen either, the problem is only when I try to power my video source from the cigarette lighter. Anything that is used to output sound and/or video seems to get interference or ground noise from that cigarette lighter.

Thanks for your help electro. I'll give it a try soon!

Tsx536

I went by radio shack. Got a inline filter, hooked it up in series to the Cigarette lighter and it all works great now!! No more interference in my portable video player!

The install was very easy. I was able to buy connectors that plugged straight into the OEM harnesses. NO cutting or splicing required!

Thanks electro and elduderino for your help on this one!

I wonder if using an inline filter on the cigarette power supply would eliminate the need for the Ground loop isolators that many people are using. Maybe someone else can comment on this.

elduderino

Two different kinds of noise.

One of my first posts here was about different kinds of noise (you may remember that our local insurance adjuster got all up in my grill about it).

Noise from the vehicle electrical system can come from three places:

1) It can come in the power wire. This can be prevented by installing filters on the wire that should have been in the unit.

2) It can arise due to the electrical ground return paths of two units not being electrically identical.

3) It can be picked up inductively through the air when certain wires are parallel or when an inductor is near a wire. This can happen on RCA's (no matter WHAT anybody says, it can), it can happen internally in a circuit board (the old old Ford pickups used to run the ammeter feed wire over the radio. When you installed a tape deck in them, the tape HEAD picked up the magnetic field noise and you had tape engine noise!), and it can happen to the inductors inside a speaker-level xover.

Back then I left out the rare 4th cause of noise: Heterodyne interference between the switching power supply frequencies of two different units. Rare, but sometimes two different units can't be in the car at the same time. This really isn't engine noise, though, because it exists with the engine off too.